JP6649101B2 - Touch roller, paper drying device and paper manufacturing method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a touch roller used for performing so-called hot-press drying in which a wet paper is pressed against a surface of a Yankee dryer roller and dried in a Yankee dryer part of a wet paper machine.

  Conventionally, when manufacturing relatively high basis weight household paper such as towel paper, there is no general-purpose wet paper machine that can be used for such thick paper. The fact is that wet paper machines used for the production of thin papers with a very low basis weight have been diverted. FIG. 2 shows an example of a wet paper machine conventionally used for producing towel paper, that is, a wet paper machine for producing thin paper such as tissue paper.

  The wet paper machine 90 shown in FIG. 2 includes a stock adjustment part 90A, a forming part 90B, a first dry part 90C, a second dry part 90D, and a winder part 90E. In the wet paper machine 90, first, in the stock adjustment part 90A, the stock supplied from the preparation device 91 is adjusted to a predetermined concentration and supplied to the forming part 90B, and then the stock supplied in the forming part 90B. , A continuous web-like wet paper WP is formed by a paper making net (circular net in the illustrated embodiment) 92, the formed wet paper WP is transferred onto a wire 93, and moisture is removed from the wet paper WP by suction by a suction box 94. After removing a predetermined amount, the endless felt F is combined with the wet paper web WP and introduced into the first dry part 90C. Then, in the first dry part 90C, the laminate of the wet paper web WP and the endless felt F is passed between a pair of opposed press rollers 95, 95 to compress and dehydrate the wet paper web WP. 2 At the entrance of the dry part 90D, the wet paper web WP is transferred and pressed against the surface of the Yankee dryer roller 97 heated to a predetermined temperature by pressing the laminate from the endless felt F side with the touch roller 96, and dried. Thus, paper DP, which is a production object, is obtained. At the outlet of the second dry part 90D, a doctor blade 98 for peeling the paper DP stuck on the surface of the Yankee dryer roller 97 from the surface and forming a so-called dry crepe on the paper DP is arranged. The continuous belt-shaped paper DP peeled from the surface of the Yankee dryer roller 97 by the doctor blade 98 is wound into a roll by the winder part 90E.

  In the case of producing paper using the wet papermaking machine 90, in order to increase the papermaking speed and improve the production efficiency, it is essential to improve the drying efficiency of the wet paper in the dry part. It is indispensable to improve the hot-press drying efficiency of wet paper in a Yankee dryer part such as 90D. The touch roller 96 in the wet paper machine 90, that is, a roller that presses the wet paper against the surface of the Yankee dryer roller at the entrance of the Yankee dryer part, can be one of the important elements for controlling the hot-press drying. . Depending on the mode of hot-press drying of the wet paper by the touch roller, inconveniences such as insufficient drying, uneven distribution of water in the width direction of the paper and wrinkling of the paper may occur.

Regarding the touch roller, for example, in Patent Document 1, in the production of single-gloss kraft paper having a basis weight of 50 to 140 g / m ² and a density of 0.55 to 0.70 g / cm ³ , wet paper is yanked at the entrance of the Yankee dryer part. It is described that the linear pressure of the touch roller at the time of pressing against the surface of the dryer roller is from 70 to 90 kg / cm in the related art, but is preferably set to 40 to 50 kg / cm in the invention described in Patent Document 1. . According to Patent Literature 1, by controlling the linear pressure, it is possible to increase the smoothness of the surface of the wet paper without losing the bulkiness and hand feeling obtained by using mechanical pulp (Patent Literature 1) [0009], [0010], [0033] and [0036] etc.).

Japanese Patent Application Laid-Open No. H11-163,086 discloses that, in the production of a nonwoven fabric for a battery separator having a basis weight of 30 to 100 g / m ² , when a fiber web formed by a wet papermaking method is hot-press dried with a Yankee dryer, the production stability is ensured. From the point of view, it is described that a touch roller is equipped with a jack for adjusting the gap with the Yankee dryer roller, and that the internal structure of the touch roller is a water-cooled structure. It is also described that the hardness to be performed is 50 or more and 85 or less, and the surface temperature of the touch roller is 110 ° C. or less (see [0026] and [0027] of Patent Document 2).

JP 2009-299208 A JP 2014-173192 A

  When producing relatively high-basis, low-density household paper such as towel paper, if the papermaking speed (wet paper transfer speed) in a wet paper machine is increased from the viewpoint of improving production efficiency, the drying target Since the wet paper is inherently difficult to dry due to its high basis weight, the drying in the Yankee dryer part cannot catch up with the increase in the papermaking speed, and there is a risk of poor drying. Since the distribution of moisture in the direction perpendicular to the transport direction becomes non-uniform, wrinkles may be formed on the paper as the product, which may cause deterioration in quality. A technique capable of efficiently producing bulky paper having a high basis weight and a low density without generating wrinkles, particularly a technique for improving a touch roller in a Yankee dryer part based on this viewpoint has not yet been provided.

  An object of the present invention is to produce a high-weight and low-density paper such as a towel paper by a wet papermaking method. The present invention relates to providing a technology capable of efficiently producing paper.

The present invention provides a method for producing paper having a basis weight of 32 g / m ² or more and a density of 0.7 g / cm ³ or less by wet papermaking while rotating around the central axis while contacting the wet paper being conveyed. A touch roller that presses paper against the surface of a Yankee dryer roller, comprising a main body having an outer peripheral surface that comes into contact with the press-contact target, wherein the main body has a diameter at a central portion in the axial direction and a diameter at an axial end. The diameter of the central portion in the axial direction is 570 to 850 mm, and the difference between the diameter of the central portion in the axial direction and the diameter of the axial end portion is 0.5 to 1. The touch roller is 5 mm.

Also, the present invention is a paper drying apparatus for heating and drying wet paper when producing paper having a basis weight of 32 g / m ² or more and a density of 0.7 g / cm ³ or less by a wet papermaking method, comprising a Yankee dryer roller, A touch roller that is disposed near the Yankee dryer roller and that rotates around the central axis while contacting the wet paper web being conveyed, and that presses the wet paper web against the surface of the Yankee dryer roller. A main body having an outer peripheral surface that comes into contact with the object to be pressed; the main body has a crown shape in which a diameter of a central portion in an axial direction is larger than a diameter of an end in an axial direction; Is a diameter of 570 to 850 mm, and a difference between the diameter of the central portion in the axial direction and the diameter of the end portion in the axial direction is 0.5 to 1.5 mm.

Further, the present invention includes a step of pressing the touch roller against one side of the wet paper web being conveyed to press the wet paper web against the surface of the Yankee dryer roller to dry the wet paper web. The basis weight is 32 g / m2. A method for producing paper having a density of ² or more and a density of 0.7 g / cm ³ or less, wherein the touch roller includes a main body having an outer peripheral surface that comes into contact with an object to be pressed, and the main body has a central portion in an axial direction. Has a crown shape whose diameter is larger than the diameter of the end portion in the axial direction, the diameter of the central portion in the axial direction is 570 to 850 mm, the diameter of the central portion in the axial direction and the diameter of the axial end portion. Is a method for producing paper having a difference of 0.5 to 1.5 mm.

  According to the present invention, when high-basis weight and low-density paper such as towel paper is manufactured by a wet papermaking method, the wet paper can be efficiently dried while suppressing the generation of wrinkles, and high-quality paper can be obtained. Provided are a touch roller, a paper drying device, and a paper manufacturing method capable of efficiently manufacturing paper.

FIG. 1 is an overall schematic diagram of an embodiment of the touch roller of the present invention. FIG. 2 is a schematic configuration diagram of a conventional wet paper machine.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. FIG. 1 shows an embodiment of the touch roller of the present invention. The touch roller 1 shown in FIG. 1 is a roller that contacts the wet paper web being conveyed and rotates around the central axis while pressing the wet paper web against the surface of the Yankee dryer roller during the production of paper by the wet papermaking method. Its use is the same as that of the touch roller 96 in the conventional wet paper machine 90 shown in FIG. That is, in the wet paper machine 90, the touch roller 1 of the present embodiment can be used instead of the touch roller 96.

  As illustrated in FIG. 1, the touch roller 1 includes a main body 2 and a rotation center shaft 3 having portions extending outward from the both ends of the main body 2 in the axial direction X in the same direction. . The main body 2 is a portion having an outer peripheral surface that comes into contact with a pressure-contact object (paper) of the touch roller 1, and covers a core metal (not shown) and the outer peripheral surface of the core metal. And an elastic layer 20 that forms The material of the cored bar is not particularly limited, and is usually made of metal. The touch roller 1 has a crown shape in which the diameter RC at the center in the axial direction X is larger than the diameter RS at the end in the axial direction X. The axial direction X is a direction in which the rotation center axis 3 extends. The diameter RC is a diameter at the center position of the main body 2 in the axial direction X, and the diameter RS is a diameter at an end position of the main body 2 in the axial direction X. The touch roller 1 (the main body 2) is formed symmetrically with respect to a virtual straight line VL that extends through the center in the axial direction X and extends in a direction (normal direction) perpendicular to the axial direction X.

The touch roller 1 is used for manufacturing “paper having a basis weight of 32 g / m ² or more and a density of 0.7 g / cm ³ or less” (hereinafter, also referred to as “specific paper”). The specified effect is exhibited only when used for the production of a specific paper having a high basis weight and a low density. A typical use of the specific paper is towel paper (also called paper towel). As is well known, towel paper is a disposable towel used to wipe off moisture and dirt attached to hands, etc., and is required to have excellent strength, water absorption and flexibility, and good touch. You. The touch roller 1 is capable of efficiently manufacturing towel paper that can meet such a demand, specifically, for example, a towel paper having a tensile strength, a water absorption degree, and a water retention within the following specific ranges. Can be.

The basis weight of the particular paper, preferably 32~100g / m ^2, more preferably 32~70g / m ^2, more preferably from 32~49g / m ^2.
The density of the specific paper is preferably 0.2 to 0.6 g / cm ³ , more preferably 0.22 to 0.5 g / cm ³ , and more preferably 0.25 to 0.4 g / cm ³ .
The thickness of the specific paper under no load is preferably 0.095 to 0.140 mm, and more preferably 0.100 to 0.135 mm.

When the specific paper is used for towel paper, its dry tensile strength, measured in accordance with JIS P8113, is preferably 0.55 to 1.30 kN / m in the machine direction (machine direction). It is more preferably 0.60 to 1.15 kN / m, and preferably 0.28 to 0.60 kN / m, and more preferably 0.32 to 0.6 kN / m in a lateral direction (a direction perpendicular to the machine direction: Cross Direction). 0.50 kN / m.
When the specific paper is used for towel paper, the wet tensile strength of the specific paper measured in accordance with JIS P8135 is preferably 0.10 to 0.50 kN / in the machine direction in the machine direction. m, more preferably 0.15 to 0.40 kN / m.

  When the specific paper is used for towel paper, the degree of water absorption is preferably 25 to 60 seconds / 10 mm, more preferably 25 to 45 seconds / 10 mm. The water absorption is measured by the Krem method measured according to JIS P8141 until the height of the immersed water reaches 10 mm.

When the specific paper is used for towel paper, the water retention is preferably 75 to 120 g / m ² , more preferably 80 to 115 g / m ² . This water retention is measured by the following method. That is, a test piece having a square shape of 100 mm × 100 mm in plan view was prepared for the evaluation object (the specific paper), and the test piece was immersed in water at 23 ° C. for 10 minutes, taken out, and subjected to the test under normal temperature and normal pressure environment. The test piece is suspended and dried so that the direction along the surface of the test piece extends along the vertical direction, and the weight of the test piece is measured when water ceases to drop from the test piece in the suspended state for 90 seconds or more. Then, the difference between the measured weight and the weight before immersion in water is calculated and converted to about 1 m ² , and the converted value is used as the water holding capacity of the evaluation object.

  The specific paper is inherently difficult to dry due to its high basis weight and the like. Therefore, in order to improve production efficiency and the like in a wet paper machine 90 as shown in FIG. ), There was a problem that the drying in the Yankee dryer part could not catch up with the speeding up of the paper making, resulting in poor drying. In addition, the specific paper manufactured using a conventional touch roller may have unintended wrinkles due to uneven distribution of water during manufacture, and the like. There were also issues in this regard.

  In order to solve the problem unique to the specific paper, in the touch roller 1 according to the present embodiment, the main body 2 having the outer peripheral surface that comes into contact with the paper (wet paper) to be pressed is set in the axial direction X thereof. Adopts a crown shape in which the diameter RC at the center is larger than the diameter RS at the end in the axial direction X, the diameter RC is 570 to 850 mm, and the difference (that is, the crown amount) r between the diameter RC and the diameter RS is Was set to 0.5 to 1.5 mm, respectively. According to the touch roller 1 of the present embodiment having such a configuration, when the specific paper represented by the towel paper is manufactured by a wet papermaking method, the wet paper is efficiently dried while suppressing the generation of wrinkles. As a result, the high-quality specific paper can be efficiently produced.

  The original use of the touch roller conventionally used in the production of towel paper is to produce a paper having a low basis weight and a small thickness as compared with towel paper, such as tissue paper, and the shaft of the conventional touch roller is used. The present inventors recognize that the diameter of the central portion in the longitudinal direction is usually about 560 mm or shorter. On the other hand, the diameter RC of the center part in the axial direction direction of the touch roller 1 of the present embodiment is 570 to 850 mm, preferably 600 to 800 mm, and more preferably 650 to 710 mm, which is larger than the conventional product. The touch roller 1 having the diameter RC in such a specific range has a larger diameter than the conventional product, so that the wet roller is used by the touch roller 1 to improve the drying efficiency of the wet paper. Even when the nip width (the contact width of the touch roller 1 at the time of pressing) is increased by increasing the linear pressure when pressing against the surface of the substrate, it can withstand the high linear pressure in terms of strength. Therefore, according to the touch roller 1, the drying efficiency when the specific paper is manufactured by the wet papermaking method can be greatly improved. If the diameter RC is less than 570 mm, the effect of improving the strength of the touch roller 1 and the effect of improving the drying efficiency are poor. If the diameter RC is more than 850 mm, the wet paper is pressed against the surface of the Yankee dryer roller when the wet paper is pressed. There is a possibility that air is mixed into the portion and wrinkles are generated due to the air.

  However, simply increasing the linear pressure when the wet paper is pressed against the surface of the Yankee dryer roller results in the wet paper being excessively compressed in the thickness direction due to the high linear pressure, and as a result, the manufacturing object There is a possibility that the characteristics of the specific paper having a high basis weight and a low density are impaired. On the other hand, the touch roller 1 of the present embodiment has a crown shape in which the diameter RC at the center in the axial direction X is larger than the diameter RS at the end in the axial direction X, and the crown amount r is smaller. 0.5 to 1.5 mm, preferably 0.6 to 1.2 mm, and more preferably 0.7 to 1.1 mm, so that even when the papermaking speed in a wet paper machine is increased, the characteristics of the specific paper can be improved. The specific paper can be efficiently produced without impairing wrinkles and while suppressing the occurrence of unintended wrinkles. The relationship between the crown amount of the touch roller of 0.5 to 1.5 mm and the expression of the effect of suppressing the generation of wrinkles on the paper is not clear, but by the fact that the crown amount is in such a specific range, the When the wet paper is pressed against the surface of the Yankee dryer roller, the contact state between the wet paper and the surface of the Yankee dryer roller is improved, whereby unevenness in drying in the width direction of the wet paper, that is, the direction perpendicular to the transport direction is reduced. It is presumed to be due to the reduction. If the crown amount r is less than 0.5 mm, the end of the wet paper may be overdried. If the crown amount r is more than 1.5 mm, the end of the wet paper may be poorly dried.

  In addition, from the viewpoint of more stably and efficiently performing the production of the bulky paper having a high basis weight and a low density, the diameter RC of the central part in the axial direction X and the axial direction The ratio of X to the total length L is preferably 0.22 to 0.28, more preferably 0.25 to 0.28, as the former RC / the latter L.

  In addition, from a similar viewpoint, the hardness of the outer peripheral surface of the main body 2 measured according to JIS K6253 is preferably 70 to 75, and more preferably 71 to 73. When the hardness of the outer peripheral surface of the main body 2, that is, the hardness of the elastic layer 20 forming the outer peripheral surface is within such a range, when the wet paper is pressed against the surface of the Yankee dryer roller by the touch roller 1 (the main body 2). In addition, since the elastic layer 20 is appropriately deformed so as not to excessively compress the specific paper in the thickness direction, the wet paper can be dried without impairing the characteristics of the specific paper having a high basis weight and a low density. Improving the efficiency will be more reliably achieved. The material of the elastic layer 20 is appropriately selected from elastic materials conventionally used for this type of elastic roller, such as natural rubber, styrene butadiene rubber, and silicone rubber, so that the hardness is 70 to 75. Is preferred.

  The present invention includes a paper drying device in addition to the touch roller described above. The paper drying apparatus of the present invention is an apparatus for heating and drying a wet paper when the specific paper is manufactured by the wet papermaking method, and is disposed near a Yankee dryer roller (rotating cylinder paper dryer). A touch roller that presses the wet paper against the surface of the Yankee dryer roller while rotating around the central axis while contacting the wet paper being conveyed, such as the above-mentioned touch roller 1 as the touch roller. The touch roller of the present invention is used. The main characteristic part of the paper drying apparatus of the present invention resides in the touch roller, and the configuration other than the touch roller such as the Yankee dryer roller can be configured similarly to a known Yankee dryer, including the arrangement of the touch roller. As one embodiment of the paper drying apparatus of the present invention, the second dry part 90D in the wet paper machine 90 shown in FIG. 2, that is, “the wet paper web WP placed on the felt F and being conveyed is moved to the felt F side by the touch roller 96. 1 is a paper drying device adapted to be pressed against the Yankee dryer roller 97. In the paper drying device, the touch roller 96 shown in FIG.

  The touch roller and the paper drying apparatus of the present invention can be used in the same manner as the touch roller and the Yankee dryer of this type in the production of the specific paper by the wet papermaking method. The present invention includes a step of pressing the touch roller against one side of the wet paper web being conveyed to press the wet paper web against the surface of the Yankee dryer roller to dry the wet web paper, thereby manufacturing the specific paper. However, in one embodiment of the method for producing paper of the present invention, the touch roller 1 shown in FIG. 1 is used as the touch roller, and the other steps are the same as those of a known wet papermaking method except for the touch roller. be able to.

  In the paper manufacturing method of the present invention, from the viewpoint of improving the drying efficiency, the linear pressure when the wet paper is pressed against the surface of the Yankee dryer roller by the touch roller is preferably 60 to 100 kN / m, and more preferably 80 kN / m. １００100 kN / m. The linear pressure of 60 to 100 kN / m is relatively high as the linear pressure of this kind of touch roller, but as described above, if the touch roller of the present invention such as the touch roller 1 shown in FIG. Even with such a high linear pressure, it can be used without any particular problem, and the specific paper can be efficiently produced.

  From a similar viewpoint, the nip width of the touch roller when the wet paper is pressed against the surface of the Yankee dryer roller by the touch roller is preferably 22 to 30 mm, and more preferably 24 to 29 mm. The nip width of such a touch roller can be achieved by setting the hardness measured according to JIS K6253 of the outer peripheral surface of the main body portion in contact with the object to be pressed to 70 to 75 as described above.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

[Examples 1 to 4 and Comparative Examples 1 to 4]
In a touch roller whose main body has a crown shape similar to that of the main body 2 shown in FIG. 1, that is, a crown shape in which the diameter at the central portion in the axial direction is larger than the diameter at the end portion in the axial direction, the dimensions of each part, etc. Are prepared. Then, in the wet paper machine 90 shown in FIG. 2, the prepared touch roller is used in place of the touch roller 96, and the papermaking speed of the wet paper is appropriately changed to obtain a basis weight of 35.0 g / m ² and a density of 0.38 g. / Cm ³ of towel paper was produced.
In the production of towel paper, 100% by mass of LBKP was used as wood pulp, and a raw disc pulp slurry having a beating degree of 400 ml according to Canadian Standard Freeness was prepared using a double disc refiner. A rosin sizing agent was added to the raw pulp slurry at a solid content concentration of 0.5% by mass per mass of pulp and aluminum sulfate at 4% by mass to prepare a raw material slurry, and the raw material slurry was subjected to wet papermaking according to a conventional method. .

(Performance evaluation)
About the towel paper manufactured in each Example and the comparative example, the generation | occurrence | production state of the wrinkle was observed visually, and it evaluated based on the following reference | standard. Based on the following criteria, it can be said that there is no practical problem if 〇 or △.
：: No wrinkles were generated at all in the machine direction of 5000 m of the obtained towel paper.
Δ: Wrinkles occurred at 1 to 3 locations per 5000 m in the paper making direction of the obtained towel paper.
×: Wrinkles were generated at four or more places per 5000 m in the paper making direction of the obtained towel paper, or paper breakage which was considered to be affected by wrinkles occurred during the paper making process.

  As shown in Table 1, in each of the examples and the comparative examples, the tendency that wrinkles became remarkable as the papermaking speed increased was common. Is suppressed. Comparative Examples 1 and 2 differ from each Example in that the diameter RC of the main body of the touch roller is out of the range of 570 to 850 mm, and Comparative Examples 3 and 4 have a crown amount of 0.5 to 1. It is different from each embodiment in that it is out of the range of 5 mm, and it is presumed that such a difference appears as a difference in the state of occurrence of wrinkles. In addition, Example 1 was the highest evaluation, while Example 2 was slightly inferior in evaluation results, mainly because of the hardness of the outer peripheral surface of the main body of the touch roller. . From a comparison between Example 1 and Example 2, it can be seen that a more appropriate range of the hardness of the outer peripheral surface of the main body is the range in Example 1 and its vicinity. Further, from a comparison between Example 1 and Examples 3 and 4, it can be seen that the diameter RC and the crown amount of the main body of the touch roller are more appropriate in the range in Example 1 and in the vicinity thereof, respectively. .

1,96 Touch Roller 2 Main Body 20 Elastic Layer 3 Rotation Center Axis 90 Wet Type Paper Machine 90A Paper Material Adjustment Part 91 Preparation Device 90B Forming Part 92 Making Net 93 Wire 94 Suction Box 90C First Dry Part 95 Press Roller 90D Second Dry part 97 Yankee dryer roller 98 Doctor blade 90E Winder part F Felt WP Wet paper DP Paper (dried wet paper)

Claims (6)

During the production of paper having a basis weight of 32 g / m ² or more and a density of 0.7 g / cm ³ or less by a wet papermaking method, the wet paper is rotated while rotating around a central axis while being in contact with the wet paper being conveyed. A touch roller pressed against the surface of the roller,
A main body having an outer peripheral surface that comes into contact with the object to be pressed; the main body has a crown shape in which a diameter of a central portion in an axial direction is larger than a diameter of an end in an axial direction; A touch roller having a diameter of 570 to 850 mm and a difference between the diameter of the central portion in the axial direction and the diameter of the end portion in the axial direction of 0.5 to 1.5 mm.   2. The touch roller according to claim 1, wherein a ratio of a diameter of the central portion in the axial direction to a total length of the main body in the axial direction is 0.22 to 0.28 as the former / the latter.   The touch roller according to claim 1, wherein the outer peripheral surface of the main body has a hardness of 70 to 75 as measured according to JIS K6253. A paper drying apparatus for heating and drying a wet paper when producing paper having a basis weight of 32 g / m ² or more and a density of 0.7 g / cm ³ or less by a wet papermaking method,
A Yankee dryer roller, comprising a touch roller disposed near the Yankee dryer roller, which is in contact with the wet paper web being conveyed and rotates around the central axis while pressing the wet paper web against the surface of the Yankee drier roller. ,
The touch roller includes a main body having an outer peripheral surface that comes into contact with the object to be pressed, and the main body has a crown shape in which a diameter at a central portion in an axial direction is larger than a diameter at an end in an axial direction. A paper drying apparatus wherein the diameter of the central portion in the axial direction is 570 to 850 mm, and the difference between the diameter of the central portion in the axial direction and the diameter of the end portion in the axial direction is 0.5 to 1.5 mm. A step of pressing the touch roller against one side of the wet paper web being conveyed to press the wet paper web against the surface of the Yankee dryer roller to dry the wet paper web has a basis weight of 32 g / m ² or more and a density of 0 0.7 g / cm ³ or less, comprising:
The touch roller includes a main body having an outer peripheral surface that comes into contact with the object to be pressed, and the main body has a crown shape in which the diameter of the central portion in the axial direction is larger than the diameter of the end in the axial direction. A method for producing paper, wherein the diameter at the central portion in the axial direction is 570 to 850 mm, and the difference between the diameter at the central portion in the axial direction and the diameter at the end in the axial direction is 0.5 to 1.5 mm.   The paper manufacturing method according to claim 5, wherein the linear pressure of the touch roller is 60 to 100 kN / m.

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